The pilot flying was slow to reduce the power to idle after flaring the aircraft for landing. Due to the excess airspeed and power, the aircraft floated, touching down with approximately 3000feet of runway remaining. Although the available 3000feet of runway remaining exceeded the unfactored estimated ground roll of 2200 feet, the aircraft was unable to stop. A touchdown speed higher than the landing reference speed (Vref), slow deployment of the thrust reversers, standing water at the intersection of the runways, friction values at the runway ends that were at or below the Transport Canada runway maintenance planning level, and limited tire tread depth likely contributed to the runway excursion. During the landing roll, the aircraft's tires hydroplaned, reducing the braking forces.Findings as to Causes and Contributing Factors The pilot flying was slow to reduce the power to idle after flaring the aircraft for landing. Due to the excess airspeed and power, the aircraft floated, touching down with approximately 3000feet of runway remaining. Although the available 3000feet of runway remaining exceeded the unfactored estimated ground roll of 2200 feet, the aircraft was unable to stop. A touchdown speed higher than the landing reference speed (Vref), slow deployment of the thrust reversers, standing water at the intersection of the runways, friction values at the runway ends that were at or below the Transport Canada runway maintenance planning level, and limited tire tread depth likely contributed to the runway excursion. During the landing roll, the aircraft's tires hydroplaned, reducing the braking forces.